FDG-PET/CT Accurate in Diagnosing Breast Cancer Recurrence

[¹⁸F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging was accurate in diagnosing breast cancer recurrence with only a small number of false-positive cases, a study published in the Journal of Clinical Oncology has shown.¹

For the study, researchers sought to investigate diagnostic accuracy of FDG-PET/CT, contrast-enhanced CT, and bone scintigraphy in patients with suspected breast cancer recurrence.

Researchers prospectively evaluated 100 women with suspected recurrence of breast cancer. Each woman underwent 1-hour and 3-hour FDG-PET/CT, contrast-enhanced CT, and bone scintigraphy within approximately 10 days. Imaging results were compared with the reference standard of biopsy results along with treatment decisions and clinical follow-up.

Researchers found that FDG-PET/CT imaging resulted in no false negatives and fewer false positives than contrast-enhanced CT and bone scintigraphy, and accuracy of results were similar between the 2 time points.

For distant recurrence, the area under the receiver operating curve was 0.99 (95% CI, 0.97 – 1) for FDG-PET/CT, 0.84 (95% CI, 0.73 – 0.94) for contrast-enhanced CT, and 0.86 (95% CI, 0.77 – 0.94) for the combined contrast-enhanced CT and bone scintigraphy. The area under the receiver operating curve represents the accuracy of a particular test. An area under the receiver operating curve of 0.90 to 1 is typically considered to have excellent accuracy, while 0.80 to 0.90 represent good accuracy.

Results also showed that 22% of the 100 patients were confirmed to have distant recurrence, of which 18 had bone involvement. Nineteen patients had local recurrence only.

Further, exploratory analyses demonstrated that FDG-PET/CT had better diagnostic accuracy than contrast-enhanced CT alone or contrast-enhanced CT combined with bone scintigraphy in diagnosing distant, bone, and local recurrence.

Reference

1. Hildebrandt MG, Gerke O, Baun C, et al. [¹⁸F]Fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in suspected recurrent breast cancer: a prospective comparative study of dual-time-point FDG-PET/CT, contrast-enhanced CT, and bone scintigraphy [published online ahead of print March 21, 2016]. J Clin Oncol. doi: 10.1200/JCO.2015.63.5185.